In means of transport, such as aircraft, buses, trains or ships, more and more electronic components, electronic assemblies and electronic equipment, which may be grouped together under the term electronics for short, are being employed. Electronics on board these means of transport are able to still further increase not only the comfort of the passengers, but also the safety on board. In operation, any form of electronics produces heat (often also referred to as waste heat) and must therefore be cooled. With regard to aircraft, electronics are often referred to as avionics (formed from the terms aviatics (aviation) and electronics).
For many decades, avionics have been grouped together in dedicated compartments (these compartments are often also referred to as avionics compartments) and cooled there with the aid of a ventilation system. In almost all larger commercial aircraft, air cooling systems which use uncooled air as the cooling medium are employed. These cooling systems, also referred to as ventilation systems, are very robust and of comparatively low mass.
Alternatively, it has been envisaged to employ a liquid cooling system for power electronics, which directly cools against the outside temperature level without a compression refrigerating machine, in contrast to galley cooling systems (for example for preserving food). This liquid cooling system is installed centrally in the middle of the aircraft in the vicinity of the ram air ducts and utilises these ram air ducts which are present.
The growing integration of information technology and other electronics results in ever-increasing thermal output densities and thereby makes increasing demands on the cooling ability of the cooling system used. A simple enlargement of the above-mentioned ventilation systems results in increased space requirement, increased mass, greater noise generation, and increased electric power consumption. The ram air ducts required for the above-described liquid cooling system are not present in the vicinity of the avionics compartment and can thus be integrated only with considerable additional outlay on manufacture together with increased structural mass.
IDE 10 2009 039 814 A1 relates to a system and method for cooling at least one heat producing device in an aircraft. The system has at least one cooling circuit. A coolant absorbs heat of the heat producing device and dissipates heat, by way of a heat dissipation device, to the surroundings of the aircraft. A temperature spreading device reduces the temperature of the coolant in a feed flow of the coolant circuit and increases the heat dissipation temperature of the heat dissipation device relative to the temperature of the coolant in an outflow of the coolant circuit.